Thank you for reporting Chromium bug.
I've noticed rendering issues in Chrome on 2019 Macbook Pro w/ Radeon GPU. But to be honest I saw severe rendering glitches even in Google Maps 3D terrain mode on that machine so I assumed Apple forgot to fix bugs in their GPU drivers and it was a normal behavior ¯\_(ツ)_/¯
I will try to provide more information. Right now I can only tell that if there were any shader compilation errors they will be shown in console.
Looking at screenshots, there might be an issue with FP32 textures, though. Instanced shaders which use vertex fetch from FP32 textures seems to produce no geometry. Instanced shaders which calculate vertex positions dynamically work just fine.
Will try to investigate this more.